The present disclosure relates to damper devices including an input element to which power from an internal combustion engine is transmitted, and an output element.
Conventionally, a double path damper that is used in association with a torque converter is known as this type of damper devices (see, e.g., JP 2012-506006 A). In this damper device, a vibration path from an engine and a lockup clutch to an output hub is divided into two parallel vibration paths B, C, and each of the two vibration paths B, C includes a pair of springs and a separate intermediate flange placed between the pair of springs. A turbine of a torque converter is connected to the intermediate flange of the vibration path B so that the resonant frequency varies between the two vibration paths. The natural frequency of the intermediate flange in the vibration path B is lower than that of the intermediate flange in the vibration path C. When the lockup clutch is engaged, engine vibration enters the two vibration paths B, C of the damper device. When the engine vibration having a certain frequency reaches the vibration path B including the intermediate flange connected to the turbine, the phase of the vibration from the intermediate flange to the output hub in the vibration path B is shifted by 180 degrees with respect to that of the input vibration. Since the natural frequency of the intermediate flange in the vibration path C is higher than that of the intermediate flange in the vibration path B, the vibration having entered the vibration path C is transmitted to the output hub without any phase shift. The vibration transmitted to the output hub through the vibration path B is thus 180 degrees out of phase with respect to that transmitted to the output hub through the vibration path C, whereby damped vibration can be obtained at the output hub.